1. Field of the Example Embodiments
Example embodiments of the present invention may relate to a method of drying an object, and an apparatus for performing the same.
2. Description of the Related Art
Generally, during the various manufacturing processes for forming an integrated circuit on a semiconductor substrate, contaminants, for example, particles may adhere to the integrated circuit. The contaminants may deteriorate electrical characteristics of the integrated circuit. Thus, a cleaning process may be performed in between the various manufacturing processes to remove the contaminants from the integrated circuit.
The cleaning process may include a chemical solution treatment process, a washing process, and/or a drying process. The chemical solution treatment process may remove the contaminants by treating the semiconductor substrate with a chemical solution. The washing process may wash the chemically treated semiconductor substrate with deionized water. The drying process may dry off the deionized water remaining on the semiconductor substrate.
A spin dryer may be used in the conventional drying method. However, droplets of deionized water on the semiconductor substrate may not be completely removed when using the conventional spin drying method. Further, vortexes generated by a rapid rotation of the semiconductor substrate during the spin drying process may contaminate the semiconductor substrate.
To solve the above-mentioned problems, a method of drying a semiconductor substrate using isopropyl alcohol (IPA) may be employed. This method utilizes the Marangoni Effect, for example, and relies on the low surface tension of IPA vapors.
According to the drying method employing the Marangoni Effect, nitrogen gas and IPA may be first heated until the nitrogen gas and the IPA are evaporated to form a gas mixture. The gas mixture may pass through a metal filter, which may remove impurities from the gas mixture. The filtered gas mixture may be heated to prevent the gas mixture from condensing. The heated gas mixture may be applied to a semiconductor substrate to dry the semiconductor substrate.
Generally, a capacitor may be formed in integrated circuits on a semiconductor substrate. To increase a capacitance of the capacitor, a plurality of capacitors, which may be formed in a small region of the semiconductor substrate, may have a height of about 18,000 Å to about 20,000 Å. When the capacitors are tall, one or more capacitors may lean and touch an adjacent capacitor, which may cause malfunction of the integrated circuit.
A method of preventing the leaning of the capacitors may include completely removing moisture between the capacitors by a drying process. In the conventional method, after the IPA vapor passes through the metal filter, the IPA vapor may be heated. However, impurities may remain in the heated IPA vapor, whereby a cohesive force between the IPA vapor and the nitrogen gas may be decreased. While the IPA vapor is supplied to a drying chamber, the IPA vapor may partially condense; thereby decreasing the amount of the IPA vapor applied to the capacitors. As a result, the moisture between the capacitors may not be completely removed, and causing the capacitors to lean.